"Adrian D. Shaw" wrote in message
...
Felly sgrifennodd John Hall :
In article ,
Adrian D. Shaw writes:
What's the difference between wet bulb and dewpoint?

Dewpoint is the temperature to which the air would have to be cooled to
become saturated, i.e. to have a relative humidity of 100%. Wet bulb
measures the degree of evaporative cooling, so that the lower the
relative humidity the greater the depression of the wet bulb reading
compared to dry bulb. At 100% RH, the dry bulb, wet bulb and dewpoint
will all be the same. For any lower RH, DB WB and, I think, WB DP.

Many thanks; yes I see you're right. There's an interesting graph at:
http://ianrpubs.unl.edu/generalag/g626.htm

This graph shows that the WB temperature could equally well be calculated
from the two variables, temperature and RH. I wonder why my WS doesn't
do that too!

Adrian
--
Adrian Shaw ais@
Adran Cyfrifiadureg, Prifysgol Cymru, aber.
Aberystwyth, Ceredigion, Cymru ac.
http://users.aber.ac.uk/ais uk

Adrian, thanks for sight of a most informative graph. Interesting also to
see it applied to problems within a pig farm!

I now have to work out how to apply it to the melting ice problem, hopefully
not of concern to the pigs.

Best regards, Roger

"Adrian D. Shaw" wrote in message
...
Felly sgrifennodd John Hall :
In article ,
Adrian D. Shaw writes:
What's the difference between wet bulb and dewpoint?

Dewpoint is the temperature to which the air would have to be cooled to
become saturated, i.e. to have a relative humidity of 100%. Wet bulb
measures the degree of evaporative cooling, so that the lower the
relative humidity the greater the depression of the wet bulb reading
compared to dry bulb. At 100% RH, the dry bulb, wet bulb and dewpoint
will all be the same. For any lower RH, DB WB and, I think, WB DP.

Many thanks; yes I see you're right. There's an interesting graph at:
http://ianrpubs.unl.edu/generalag/g626.htm

This graph shows that the WB temperature could equally well be calculated
from the two variables, temperature and RH. I wonder why my WS doesn't
do that too!

Adrian
--
Adrian Shaw ais@
Adran Cyfrifiadureg, Prifysgol Cymru, aber.
Aberystwyth, Ceredigion, Cymru ac.
http://users.aber.ac.uk/ais uk

Adrian, thanks for sight of a most informative graph. Interesting also to
see it applied to problems within a pig farm!

I now have to work out how to apply it to the melting ice problem, hopefully
not of concern to the pigs.

Best regards, Roger

"Adrian D. Shaw" wrote in message
...
Felly sgrifennodd John Hall :
In article ,
Adrian D. Shaw writes:
What's the difference between wet bulb and dewpoint?

Dewpoint is the temperature to which the air would have to be cooled to
become saturated, i.e. to have a relative humidity of 100%. Wet bulb
measures the degree of evaporative cooling, so that the lower the
relative humidity the greater the depression of the wet bulb reading
compared to dry bulb. At 100% RH, the dry bulb, wet bulb and dewpoint
will all be the same. For any lower RH, DB WB and, I think, WB DP.

Many thanks; yes I see you're right. There's an interesting graph at:
http://ianrpubs.unl.edu/generalag/g626.htm

This graph shows that the WB temperature could equally well be calculated
from the two variables, temperature and RH. I wonder why my WS doesn't
do that too!

Adrian
--
Adrian Shaw ais@
Adran Cyfrifiadureg, Prifysgol Cymru, aber.
Aberystwyth, Ceredigion, Cymru ac.
http://users.aber.ac.uk/ais uk

Adrian, thanks for sight of a most informative graph. Interesting also to
see it applied to problems within a pig farm!

I now have to work out how to apply it to the melting ice problem, hopefully
not of concern to the pigs.

Best regards, Roger